相关论文: Advanced technique for measuring relative length c…
We report on the realization of a capacitive dilatometer, designed for high-resolution measurements of length changes of a material for temperatures 1.4 K $\leq T \leq$ 300 K and hydrostatic pressure $P \leq$ 250 MPa. Helium ($^4$He) is…
We present high resolution thermal expansion measurement data obtained with high relative sensitivity of $\Delta$L$/$L = 10$^{-9}$ and accuracy of $\pm$2$\%$ using closed cycle refrigerators employing two different dilatometers. The data…
We describe the design, construction, calibration, and operation of a relatively simple differential capacitive dilatometer suitable for measurements of thermal expansion and magnetostriction from 300 K to below 1 K with a low-temperature…
Recent high-dispersion spectroscopy from ground-based telescopes and high-precision spectroscopy from space observatories have enabled atmospheric observations of substellar objects, such as brown dwarfs and hot gaseous exoplanets, with…
The existence of a static lengthscale that grows in accordance with the dramatic slowing down observed at the glass transition is a subject of intense interest. A recent publication compared two proposals for this length scale, one based on…
Recent developments of the AC-calorimetric technique adapted for the needs of high pressure experiments are discussed. A semi-quantitative measurement of the specific heat with a Bridgman-type of pressure cell as well as a diamond anvil…
We introduce a new stress dilatometer with exactly the same size and weight as the world's smallest miniature capacitance dilatometer (height x width x depth = 15 mmx14 mmx15 mm, weight: 12 g). To develop this new device, only a single part…
We describe a set-up for studying adsorption of helium in silica aerogels, where the adsorbed amount is easily and precisely controlled by varying the temperature of a gas reservoir between 80 K and 180 K. We present validation experiments…
A concentration-saturated helium mixture at the melting pressure consists of two liquid phases and one or two solid phases. The equilibrium system is univariant, whose properties depend uniquely on temperature. Four coexisting phases can…
We present a Taylor-Couette facility designed to investigate angular momentum transport over a wide range of Reynolds numbers, from moderate regimes in gases to extreme and potentially quantum regimes in cryogenic helium. The apparatus…
The excess work performed in a heat-engine process with given finite operation time \tau is bounded by the thermodynamic length, which measures the distance during the relaxation along a path in the space of the thermodynamic state.…
Accurately measuring the magnetocaloric effect is necessary to foster the development of magnetic refrigeration devices. However, current methods are inconvenient, requiring different instruments to measure each individual property or a…
We report a new design of temperature-modulated dilatometer, which obtains the linear thermal expansion coefficient by measuring the oscillating changes of the sample's length and temperature by a piezobender and a thermocouple,…
Thermal expansion and magnetostriction are directional dependent thermodynamic quantities. For the characterization of novel quantum phases of matter it is required to study materials under multi-extreme conditions, in particular down to…
The dramatic dynamic slowing down associated with the glass transition is considered by many to be related to the existence of a static length scale that grows when temperature decreases. Defining, identifying and measuring such a length is…
The influence of hydrostatic pressure up to P=1.05 GPa on resistivity R, excess conductivity ${\sigma}'(T)$ and pseudogap ${\Delta}*(T)$ is studied in slightly doped single crystals of YBa2Cu3O7-${\delta} (Tc=49.2 K, {\delta}~ 0.5)$. The…
Thermal expansion, or dilation, is closely related to the specific heat, and provides useful information regarding material properties. The accurate measurement of dilation in confined spaces coupled with other limiting experimental…
Dielectric response in methanol measured in wide pressure and temperature range ($P < 6.0$ GPa; 100 K $<T<$ 360 K) reveals a series of anomalies which can be interpreted as a transformation between several solid phases of methanol including…
A new set-up to measure acoustic wave velocities through deforming rock samples at high pressures (up to 1000 MPa), temperatures (up to 700$^\circ$C) and differential stress (up to 1500 MPa) has been developed in a recently refurbished gas…
We discuss two main universal dynamic crossovers in a liquid that correspond to relaxation times of 1 ps and $10^{-7}-10^{-6}$ s. We introduce the concept of liquid elasticity length $d_{el}$. At room temperature, $d_{el}$ is several \AA in…